Machine tool

Claim 2

A machine tool (10) having a rotatable turret (200) with an end face (203) extending transversely to the axis of rotation (B) of said turret and a side face (204) extending transversely to said end face, drive means (600) for transmitting drive forces through said turret to an output location between said end and side faces of said turret, said machine tool being characterized by toolholder means (300) for rotating a cutting tool (T) about a first axis (C of FIG. 7) extending perpendicular to the axis (B) of rotation of said turret when said toolholder means is mounted on said end face (203) of said turret and for rotating a cutting tool (T) about a second axis (C of FIG. 10) extending parallel to the axis of rotation (B) of said turret when said toolholder means is mounted on said side face (204) of said turret.

Claim 3

A machine tool as set forth in claim 1 wherein said drive means (600) includes a drive gear (601) rotatable about a third axis (G) which extends at an acute angle to said first and second axes (C), said toolholder means (300) including a driven gear (301) which is disposed in meshing engagement with said drive gear and is rotatable about said first axis (C of FIG. 7) by said drive gear when said toolholder means is mounted on said end face of said turret (200), said driven gear (301) being disposed in meshing engagement with said drive gear (601) and being rotatable about said second axis (C of FIG. 10) by said drive gear when said toolholder means is mounted on said side face of said turret.

Claim 4

A machine tool (10) having a rotatable turret (200) with an end face (203) extending transversely to the axis of rotation (B) of said turret and a side face (204) extending transversely to said end face, said turret (200) including a base (201), a head portion (202) upon which said end and side faces (203, 204) of said turret are disposed, drive means (600) for transmitting drive forces through said turret to an output location between said end and side faces of said turret, said drive means (600) including a first drive gear (615) rotatably mounted on said base (201) of said turret and a second drive gear (616) rotatably mounted on the head portion of said turret, said machine tool being characterized by toolholder means (300) for rotating a cutting tool (T) about a first axis (C of FIG. 7) extending perpendicular to the axis (B) of rotation of said turret when said toolholder means is mounted on said end face (203) of said turret and for rotating a cutting tool (5) about a second axis (C of FIG. 10) extending parallel to the axis of rotation (B) of said turret when said toolholder means is mounted on said side face (204) of said turret, said head portion of said turret being rotatable relative to said base between a first operating position in which said toolholder means is operable to rotate a cutting tool and any one of a plurality of operating positions in which said toolholder means is ineffective to rotate a cutting tool, and retainer means (238) for holding said second drive gear (616) in a predetermined orientation in which teeth on said second drive gear are positioned for meshing engagement with teeth on said first drive gear (615), said retainer means (238) holding said second drive gear (616) in the predetermined orientation during rotation of said head portion of said turret relative to said base and movement of said second drive gear from said first operating position through said plurality of operating positions, said retainer means (238) releasing said second drive gear (616) for rotation relative to said head portion of said turret upon movement of said second drive gear from one of said plurality of operating positions to said first operating position to enable drive forces to be transmitted from said first drive gear to said second drive gear to rotate said toolholder means (300).

Claim 5

A machine tool (10) having a rotatable turret (200) with an end face (203) extending transversely to the axis of rotation (B) of said turret and a side face (204) extending transversely to said end face, said turret (200) including a base (201), a head portion (202) upon which said end and side faces (203, 204) of said turret are disposed, drive means (600) for transmitting drive forces through said turret to an output location between said end and side faces of said turret, said drive means (600) including a first drive gear (615) rotatably mounted on said base (201) of said turret and a second drive gear (616) rotatably mounted on the head portion of said turret, said machine tool being characterized by toolholder means (300) for rotating a cutting tool (T) about a first axis (C of FIG. 7) extending perpendicular to the axis (B) of rotation of said turret when said toolholder means is mounted on said end face (203) of said turret and for rotating a cutting tool (5) about a second axis (C of FIG. 10) extending parallel to the axis of rotation (B) of said turret when said toolholder means is mounted on said side face (204) of said turret, said head portion of said turret being rotatable relative to said base between a first operating position in which said toolholder means is operable to rotate a cutting tool and any one of a plurality of operating positions in which said toolholder means is ineffective to rotate a cutting tool, and retainer means (238) for holding said second drive gear (616) in a predetermined orientation in which teeth on said second drive gear are positioned for meshing engagement with teeth on said first drive gear (615), said retainer means (238) holding said second drive gear (616) in the predetermined orientation during rotation of said head portion of said turret relative to said base and movement of said second drive gear from said first operating position through said plurality of operating positions, said retainer means (238) releasing said second drive gear (616) for rotation relative to said head portion of said turret upon movement of said second drive gear from one of said plurality of operating positions to said first operating position to enable drive forces to be transmitted from said first drive gear to said second drive gear to rotate said toolholder means (300).

Claim 6

A machine tool as set forth in claim 3 wherein said drive means (600) includes a drive gear (601) rotatable about a third axis (G) which extends at an acute angle to said first and second axes (C), said toolholder means (300) including a driven gear (301) which is disposed in meshing engagement with said drive gear and is rotatable about said first axis (C of FIG. 7) by said drive gear when said toolholder means is mounted on said end face of said turret (200), said driven gear (301) being disposed in meshing engagement with said drive gear (601) and being rotatable about said second axis (C of FIG. 10) by said drive gear when said toolholder means is mounted on said side face of said turret.

Claim 7

A machine tool as set forth in claim 3 further including first actuator means (400) mounted adjacent to said end face (203) of said turret (200) for operating said toolholder means (300) from an engaged condition holding a cutting tool (T) to a released condition in which the cutting tool can be removed from said toolholder means when said toolholder means is mounted on said end face (203) of said turret, and second actuator means (500) mounted adjacent to said side face (204) of said turret for operating said toolholder means (300) from the engaged condition to the released condition when said toolholder means is mounted on said side face (204) of said turret.

Claim 8

An apparatus as set forth in claim 3 further including nozzle means (621) disposed on said toolholder means (300) for directing a flow of coolant toward said first axis (C of FIG. 7) when said toolholder means is mounted on said end face (203) of said turret (200) and for directing a flow of coolant toward said second axis (C of FIG. 10) when said toolholder means is mounted on said side face (204) of said turret.

Claim 9

An apparatus as set forth in claim 6 further including passage means (242, 243, 245, 246, 623) for conducting a flow of coolant through said side face (204) of said turret (200) to said nozzle means (621) when said toolholder means (300) is mounted on said end face (203) of said turret (200) and for conducting a flow of coolant through said end face (203) of said turret to said nozzle when said toolholder means is mounted on said side face (204) of said turret.

Claim 10

A machine tool as set forth in claim 3 wherein said drive means includes means (216, 217) for rotating said first drive gear (615) to a predetermined position to orient the teeth on said first drive gear (615) for meshing engagement with the teeth on said second drive gear (616).

Claim 11

A machine tool as set forth in claim 3 wherein said retainer means includes an arcuate retainer surface (237) connected with said base (201) and extending through a portion of a circle and follower surface means (606) connected with said second drive gear (616) for engaging said retainer surface (237) during movement of said second drive gear from said first operating position through said plurality of operating positions to hold said second drive gear (616) against rotation relative to said head portion (202) of said turret and for moving out of engagement with said retainer surface (237) during rotation of said head portion of said turret to move said second drive gear from one of said plurality of operating positions to said first operating position to thereby release said second drive gear (616) for rotation relative to said head portion fo said turret.

Claim 12

An apparatus as set forth in claim 3 wherein said drive means includes means (618) for moving said first drive gear (615) axially between a first position (FIG. 5) in which said first and second drive gears (615, 616) are engaged when said second drive gear (616) is at said first operating position and a second position (FIG. 6) in which said first and second drive gears are disengaged when said second drive gear is at said first operating position.

Claim 13

A machine tool as set forth in claim 10 wherein said drive means includes a third drive gear (601) and coupling means (603) for connecting said third drive gear with said second drive gear (616) for rotation therewith relative to said head portion (202) of said turret, said toolholder means including a driven gear (301) which is disposed in meshing engagement with said third drive gear (601) and is rotatable about said first axis (C of FIG. 7) by said third drive gear (601) during rotation of said first and second drive gears (615, 616) when said toolholder means is mounted on said end face (203) of said turret, said coupling means (603) being releasable to enable said third drive gear (601) to be disconnected from said second drive gear (616) to release said toolholder means (300) for movement from a mounting position on the end face (203) of said turret to a mounting position on the side face (204) of said turret, said driven gear (301) being disposed in meshing engagement with said third drive gear (601) and being rotatable about said second axis (C of FIG. 10) by said third drive gear (601) during rotation of said first and second drive gears when said toolholder means is mounted on said side face (204) of said turret.

Claim 14

A machine tool (10) having a rotatable turret (200) with an end face (203) extending transversely to the axis of rotation (B) of said turret and a side face (204) extending transversely to said end face, drive means (600) for transmitting drive forces through said turret to an output location between said end and side faces of said turret, said machine tool being characterized by toolholder means (300) for rotating a cutting tool (T) about a first axis (C of FIG. 7) extending perpendicular to the axis (B) of rotation of said turret when said toolholder means is mounted on said end face (203) of said turret and for rotating a cutting tool (T) about a second axis (C of FIG. 10) extending parallel to the axis of rotation (B) of said turret when said toolholder means is mounted on said side face (204) of said turret, first actuator means (400) mounted adjacent to said end face (203) of said turret (200) for operating said toolholder means (300) from an engaged condition holding a cutting tool (T) to a released condition in which the cutting tool can be removed from said toolholder means when said toolholder means is mounted on said end face (203) of said turret, and second actuator means (500) mounted adjacent to said side face (204) of said turret for operating said toolholder means (300) from the engaged condition to the released condition when said toolholder means is mounted on said side face (204) of said turret.

Claim 15

A machine tool (10) having a rotatable turret (200) with an end face (203) extending transversely to the axis of rotation (B) of said turret and a side face (204) extending transversely to said end face, drive means (600) for transmitting drive forces through said turret to an output location between said end and side faces of said turret, said machine tool being characterized by toolholder means (300) for rotating a cutting tool (T) about a first axis (C of FIG. 7) extending perpendicular to the axis (B) of rotation of said turret when said toolholder means is mounted on said end face (203) of said turret and for rotating a cutting tool (T) about a second axis (C of FIG. 10) extending parallel to the axis of rotation (B) of said turret when said toolholder means is mounted on said side face (204) of said turret, first actuator means (400) mounted adjacent to said end face (203) of said turret (200) for operating said toolholder means (300) from an engaged condition holding a cutting tool (T) to a released condition in which the cutting tool can be removed from said toolholder means when said toolholder means is mounted on said end face (203) of said turret, and second actuator means (500) mounted adjacent to said side face (204) of said turret for operating said toolholder means (300) from the engaged condition to the released condition when said toolholder means is mounted on said side face (204) of said turret.

Claim 16

An apparatus as set forth in claim 12 further including nozzle means (621) disposed on said toolholder means (300) for directing a flow of coolant toward said first axis (C of FIG. 7) when said toolholder means is mounted on said end face (203) of said turret (200) and for directing a flow of coolant toward said second axis (C of FIG. 10) when said toolholder means is mounted on said side face (204) of said turret.

Claim 17

An apparatus as set forth in claim 12 further including passage means (242, 243, 245, 246, 623) for conducting a flow of coolant through said side face (204) of said turret (200) to said nozzle means (621) when said toolholder means (300) is mounted on said end face (203) of said turret (200) and for conducting a flow of coolant through said end face (203) of said turret to said nozzle when said toolholder means is mounted on said side face (204) of said turret.

Claim 18

A machine tool as set forth in claim 12 wherein said turret includes a base (201), a head portion (202) upon which said side and end faces (203, 204) of said turret are disposed, said head portion (202) of said turret being rotatable relative to said base (201) and said first and second actuator means (400, 500) to move said toolholder means into and out of alignment with said first and second actuator means.

Claim 19

A machine tool (10) having a rotatable turret (200) with an end face (203) extending transversely to the axis of rotation (B) of said turret and a side face (204) extending transversely to said end face, drive means (600) for transmitting drive forces through said turret to an output location between said end and side faces of said turret, said machine tool being characterized by toolholder means (300) for rotating a cutting tool (T) about a first axis (C of FIG. 7) extending perpendicular to the axis (B) of rotation of said turret when said toolholder is mounted on said end face (203) of said turret and for rotating a cutting tool (T) about a second axis (C of FIG. 10) extending parallel to the axis of rotation (B) of said turret when said toolholder means is mounted on said side face (204) of said turret, said drive means (600) including a drive gear (601) rotatable about a third axis (G) which extends at an acute angle to said first and second axes (C), said toolholder means (300) including a driven gear (301) which is disposed in meshing engagement with said drive gear and is rotatable about said first axis (C of FIG. 7) by said drive gear when said toolholder means is mounted on said end face of said turret (200), said driven gear (301) being disposed in meshing engagement with said driven gear (601) and being rotatable about said second axis (C of FIG. 10) by said drive gear when said toolholder means is mounted on said side face of said turret, and nozzle means (621) disposed on side of said drive gear (601) opposite from said toolholder means (300) for directing a flow of coolant toward said first axis (C of FIG. 7) when said toolholder means is mounted on said end face (203) of said turret (200) and for directing a flow of coolant toward said second axis (C of FIG. 10) when said toolholder means is mounted on said side face (204) of said turret.

Claim 20

A machine tool (10) having a rotatable turret (200) with an end face (203) extending transversely to the axis of rotation (B) of said turret and a side face (204) extending transversely to said end face, drive means (600) for transmitting drive forces through said turret to an output location between said end and side faces of said turret, said machine tool being characterized by toolholder means (300) for rotating a cutting tool (T) about a first axis (C of FIG. 7) extending perpendicular to the axis (B) of rotation of said turret when said toolholder is mounted on said end face (203) of said turret and for rotating a cutting tool (T) about a second axis (C of FIG. 10) extending parallel to the axis of rotation (B) of said turret when said toolholder means is mounted on said side face (204) of said turret, said drive means (600) including a drive gear (601) rotatable about a third axis (G) which extends at an acute angle to said first and second axes (C), said toolholder means (300) including a driven gear (301) which is disposed in meshing engagement with said drive gear and is rotatable about said first axis (C of FIG. 7) by said drive gear when said toolholder means is mounted on said end face of said turret (200), said driven gear (301) being disposed in meshing engagement with said driven gear (601) and being rotatable about said second axis (C of FIG. 10) by said drive gear when said toolholder means is mounted on said side face of said turret, and nozzle means (621) disposed on side of said drive gear (601) opposite from said toolholder means (300) for directing a flow of coolant toward said first axis (C of FIG. 7) when said toolholder means is mounted on said end face (203) of said turret (200) and for directing a flow of coolant toward said second axis (C of FIG. 10) when said toolholder means is mounted on said side face (204) of said turret.

Claim 21

An apparatus as set forth in claim 16 further including passage means (242, 243, 245, 246, 623) for conducting a flow of coolant through sid side face (204) of said turret (200) to said nozzle means (621) when said toolholder means (300) is mounted on said end face (203) of said turret (200) and for conducting a flow of coolant through said end face (203) of said turret to said nozzle when said toolholder means is mounted on said side face (204) of said turret.

Claim 22

A machine tool as set forth in claim 16 further including retainer means (238) for holding said drive gear (601) against rotation about said third axis (G) during rotation of said turret, for holding said driven gear (301) against rotation about said first axis (C) during rotation of said turret with said toolholder means mounted on said end face, and for holding said driven gear (301) against rotation about said second axis (C) during rotation of said turret with said toolholder means mounted on said side face (204).

Claim 23

A machine tool as set forth in claim 18 wherein said turret (200) includes a base (201) and a head portion (202) which is rotatable relative to said base, said end and side faces (203, 204) of said turret being disposed on said head portion for rotation therewith relative to said base, said retainer means includes first retainer surface means (606) connected with said drive gear (601) for rotation therewith during rotation of said drive gear about said third axis (G) and second retainer surface means (237) connected to said base of said turret and engageable by said first retainer surface means (606) during rotation of said head portion of said turret relative to said base.

Claim 24

A machine tool as set forth in claim 16 wherein said drive means includes a drive shaft (602) rotatable about the third axis (G) and coupling means (603) for connecting said drive gear with said drive shaft, said coupling means being releasable to enable said drive and driven gears (601, 301) to be disconnected from said drive shaft (602) to change the mounting location of said toolholder means (300) between said end and side faces (203, 204) of said turret (200).

Claim 25

A machine tool as set forth in claim 20 further including housing means (624) for maintaining said drive and driven gears (601, 301) in meshing engagement during a change in the mounting location of said toolholder means (300) between said and side faces of said turret, said coupling means including index surface means (631, 632) for enabling said drive gear to be connected with said drive shaft only when said drive and driven gears (601, 301) are in a predetermined orientation relative to said drive shaft (602).

Claim 26

A machine tool (10) having a rotatable turret (200) with an end face (203) extending transversely to the axis of rotation (B) of said turret and a side face (204) extending trasnversely to said end face, driven means (600) for transmitting drive forces through said turret to an output location between said end and side faces of said turret, said machine tool being characterized by toolholder means (300) for rotating a cutting tool (T) about a first axis (C of FIG. 7) extending perpendicular to the axis (B) of rotation of said turret when said toolholder means is mounted on said end face (203) of said turret and for rotating a cutting tool (T) about a second axis (C of FIG. 10) extending parallel to the axis of rotation (B) of said turret when said toolholder means is mounted on said side face (204) of said turret, said drive means (600) including a drive gear (601) rotatable about a third axis (G) which extends at an acute angle to said first and second axes (C), said toolholder means (300) including a driven gear (301) which is disposed in meshing engagement with said drive gear and is rotatable about said first axis (C of FIG. 7) by said drive gear when said toolholder means is mounted on said end face of said turret (200), said driven gear (301) being disposed in meshing engagement with said driven gear (601) and being rotatable about said second axis (C of FIG. 10) by said drive gear when said toolholder means is mounted on said side face of said turret, retainer means (238) for holding said drive gear (601) against rotation about said third axis (G) during rotation of said turret, for holding side driven gear (301) against rotation about said first axis (C) during rotation of said turret with said toolholder means mounted on said end face, and for holding said driven gear (301) against rotation about said second axis (C) during rotation of said turret with said toolholder means mounted on said side face (204).

Claim 27

A machine tool (10) having a rotatable turret (200) with an end face (203) extending transversely to the axis of rotation (B) of said turret and a side face (204) extending trasnversely to said end face, driven means (600) for transmitting drive forces through said turret to an output location between said end and side faces of said turret, said machine tool being characterized by toolholder means (300) for rotating a cutting tool (T) about a first axis (C of FIG. 7) extending perpendicular to the axis (B) of rotation of said turret when said toolholder means is mounted on said end face (203) of said turret and for rotating a cutting tool (T) about a second axis (C of FIG. 10) extending parallel to the axis of rotation (B) of said turret when said toolholder means is mounted on said side face (204) of said turret, said drive means (600) including a drive gear (601) rotatable about a third axis (G) which extends at an acute angle to said first and second axes (C), said toolholder means (300) including a driven gear (301) which is disposed in meshing engagement with said drive gear and is rotatable about said first axis (C of FIG. 7) by said drive gear when said toolholder means is mounted on said end face of said turret (200), said driven gear (301) being disposed in meshing engagement with said driven gear (601) and being rotatable about said second axis (C of FIG. 10) by said drive gear when said toolholder means is mounted on said side face of said turret, retainer means (238) for holding said drive gear (601) against rotation about said third axis (G) during rotation of said turret, for holding side driven gear (301) against rotation about said first axis (C) during rotation of said turret with said toolholder means mounted on said end face, and for holding said driven gear (301) against rotation about said second axis (C) during rotation of said turret with said toolholder means mounted on said side face (204).

Claim 28

A machine tool as set forth in claim 22 wherein said turret (200) includes a base (201) and a head portion (202) which is rotatable relative to said base, said end and side faces (203, 204) of said turret being disposed on said head portion for rotation therewith relative to said base, said retainer means includes first retainer surface means (606) connected with said drive gear (601) for rotation therewith during rotation of said drive gear about said third axis (G) and second retainer surface means (237) connected to said base of said turret and engageable by said first retainer surface means (606) during rotation of said head portion of said turret relative to said base.

Claim 29

A machine tool as set forth in claim 22 wherein said drive means includes a drive shaft (602) rotatable about the third axis (G) and coupling means (603) for connecting said drive gear with said drive shaft, said coupling means being releasable to enable said driven and driven gears (601, 301) to be disconnected from said drive shaft (602) to change the mounting location of said toolholder means (300) between said end and side faces (203, 204) of said turret (200).

Claim 30

A machine tool (10) having a rotatable turret (200) with an end face (203) extending transversely to the axis of rotation (B) of said turret and a side face (204) extending transversely to said end face, drive means (600) for transmitting drive forces through said turret to an output location between said end and side faces of said turret, said machine tool being characterized by toolholder means (300) for rotating a cutting tool (T) about a first axis (C of FIG. 7) extending perpendicular to the axis (B) of rotation of said turret when said toolholder means is mounted on said end face (203) of said turret and for rotating a cutting tool (T) about a second axis (C of FIG. 10) extending parallel to the axis of rotation (B) of said turret when said toolholder means is mounted on said side face (204) of said turret, said drive means (600) including a drive gear (601) rotatable about a third axis (G) which extends at an acute angle to said first and second axes (C), said toolholder means (300) including a driven gear (301) which is disposed in meshing engagement with said drive gear and is rotatable about said first axis (C of FIG. 7) by said drive gear when said toolholder means is mounted on said end face of said turret (200), said driven gear (301) being disposed in meshing engagement with said drive gear (601) and being rotatable about said second axis (C of FIG. 10) by said drive gear when said toolholder means is mounted on said side face of said turret, said drive means including a drive shaft (602) rotatable about the third axis (G) and coupling means (603) for connecting said drive gear with said drive shaft, said coupling means being releasable to enable said drive and driven gears (601, 301) to be disconnected from said drive shaft (602) to change the mounting location of said toolholder means (300) between said end and side faces (203, 204) of said turret (200).

Claim 31

A machine tool (10) having a rotatable turret (200) with an end face (203) extending transversely to the axis of rotation (B) of said turret and a side face (204) extending transversely to said end face, drive means (600) for transmitting drive forces through said turret to an output location between said end and side faces of said turret, said machine tool being characterized by toolholder means (300) for rotating a cutting tool (T) about a first axis (C of FIG. 7) extending perpendicular to the axis (B) of rotation of said turret when said toolholder means is mounted on said end face (203) of said turret and for rotating a cutting tool (T) about a second axis (C of FIG. 10) extending parallel to the axis of rotation (B) of said turret when said toolholder means is mounted on said side face (204) of said turret, said drive means (600) including a drive gear (601) rotatable about a third axis (G) which extends at an acute angle to said first and second axes (C), said toolholder means (300) including a driven gear (301) which is disposed in meshing engagement with said drive gear and is rotatable about said first axis (C of FIG. 7) by said drive gear when said toolholder means is mounted on said end face of said turret (200), said driven gear (301) being disposed in meshing engagement with said drive gear (601) and being rotatable about said second axis (C of FIG. 10) by said drive gear when said toolholder means is mounted on said side face of said turret, said drive means including a drive shaft (602) rotatable about the third axis (G) and coupling means (603) for connecting said drive gear with said drive shaft, said coupling means being releasable to enable said drive and driven gears (601, 301) to be disconnected from said drive shaft (602) to change the mounting location of said toolholder means (300) between said end and side faces (203, 204) of said turret (200).

Claim 32

A machine tool having a base (201), a turret head (202) rotatably mounted on said base, toolholder means (300) mounted on said turret head, drive means (600) for transmitting drive forces from said base to said toolholder means, said drive means including a first drive gear (615) rotatably mounted on said base and a second drive gear (616) rotatably mounted on said turret head, said turret head being rotatable relative to said base between a first operating position in which said first and second drive gears are in meshing engagement and said toolholder means is operable to rotate a cutting tool under the influence of drive forces transmitted by said first ands econd drive gears and any one of a plurality of operating positions in which said first and second drive gears are out of meshing engagement and said toolholder means is ineffective to rotate a cutting tool, said machine tool being characterized by retainer means (238) for holding said second drive gear (616) in a predetermined orientation in which teeth on said second drive gear are positioned for meshing engagement with teeth on said first drive gear (615) during rotation of said turret head relative to said base and movement of said second drive gear from said first operating position through said plurality of operating positions.

Claim 33

A machine tool having a base (201), a turret head (202) rotatably mounted on said base, toolholder means (300) mounted on said turret head, drive means (600) for transmitting drive forces from said base to said toolholder means, said drive means including a first drive gear (615) rotatably mounted on said base and a second drive gear (616) rotatably mounted on said turret head, said turret head being rotatable relative to said base between a first operating position in which said first and second drive gears are in meshing engagement and said toolholder means is operable to rotate a cutting tool under the influence of drive forces transmitted by said first ands econd drive gears and any one of a plurality of operating positions in which said first and second drive gears are out of meshing engagement and said toolholder means is ineffective to rotate a cutting tool, said machine tool being characterized by retainer means (238) for holding said second drive gear (616) in a predetermined orientation in which teeth on said second drive gear are positioned for meshing engagement with teeth on said first drive gear (615) during rotation of said turret head relative to said base and movement of said second drive gear from said first operating position through said plurality of operating positions.

Claim 34

A machine tool as set forth in claim 26 wherein said retainer means (238) releases said second drive gear (616) for rotation relative to said turret head (202) upon movement of said second drive gear from one of said plurality of operating positions to said first operating position to enable drive forces to be transmitted from said first drive gear to said second drive gear to rotate said toolholder means (300).

Claim 35

A machine tool as set forth in claim 26 wherein said drive means includes means (216, 217) for rotating said first drive gear (615) to a predetermined position to orient the teeth on said first drive gear (615) for meshing engagement with the teeth on said second drive gear (616).

Claim 36

A machine tool as set forth in claim 26 wherein said retainer means includes an arcuate retainer surface (237) connected with said base (201) and extending through a portion of a circle and follower surface means (606) connected with said second drive gear (616) for engaging said retainer surface (237) during movement of said second drive gear from said first operating position through said plurality of operating positions to hold said second drive gear (616) against rotation relative to said turret head (202) and for moving out of engagement with said retainer surface (237) during rotation of said turret head to move said second drive gear from one of said plurality of operating positions to said first operating position to thereby release said second drive gear (616) for rotation relative to said turret head.

Claim 37

An apparatus as set forth in claim 36 wherein said drive means includes means (618) for moving said first drive gear (615) axially between a first position (FIG. 5) in which said first and second drive gears (615, 616) are engaged when said second drive gear (616) is at said first operating position and a second position (FIG. 6) in which said first and second drive gears are disengaged when said second drive gear is at said first operating position.

Claim 38

A machine tool as set forth in claim 30 wherein said drive means includes a third drive gear (601) and coupling means (603) for connecting said third drive gear with said second drive gear (616) for rotation therewith relative to said turret head (202), said toolholder means including a driven gear (301) which is disposed in meshing engagement with said third drive gear (601) and is rotatable by said third drive gear (601) during rotation of said first and second drive gears (615, 616) when said toolholder means is mounted on said turret head, said coupling means (603) being releasable to enable said third drive gear (601) to be disconnected from said second drive gear (616) to release said toolholder means (300) for movement from a mounting position on said turret head.